SU1488711A1 - Device for monitoring temperature of gas turbine engine rotor blades - Google Patents

Description

The invention relates to a measurement technique, namely to infinity. The invention relates to a measurement technique, namely to contactless temperature measurement from thermal radiation of objects using pyrometers.

The purpose of the invention is to improve the accuracy of determining the presence of overheating and enhanced functionality.

On the drawing shows a functional diagram of the proposed device.

The device contains a photoelectric pyrometer 1, amplifier 2, first 3, second 4 and third 5 keys, peak detector 6, analog-to-digital converter (ADC) 7, block 8 vy2

This method measures temperature by thermal radiation of objects using pyrometers, and can be used to measure the parameters of gas turbine engines (GTE). The purpose of the invention is to improve the accuracy of determining the presence of overheating and enhanced functionality. The fact of overheating of any working blades of the CCD is determined not only by electrical signals of increased amplitude proportional to the temperature of the working blades recorded during the passage of the working blades * in the viewing zone of the pyrometer, but also by the duration of this electrical signal. This will filter out short duration interference. In addition, the device allows to measure the average maximum temperature of the blades for one revolution of the GTE rotor. 1 il.

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equalization, linearization unit 9, first 10 and second 11 comparators, voltage reference source 12, inverter 13, first 14 and second 15 integrators, counter 16 of the number of blades, standby multivibrator 17, overheating indicator 18, position sensor 19 associated with gauges ( not shown) installed on the rotor of a gas turbine engine (GTE), shaper 20 measurement intervals and the sensor 21 of the origin, associated with a marker located on the shaft of the GTE.

The device works as follows.

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A photoelectric pyrometer G converts the thermal radiation of GTE working blades (not shown) passing through its sight zone into an electrical signal whose amplitude is proportional to the temperature of the GTE blades ”From the output of the photoelectric pyrometer 1 electrical signal

through amplifier 2 and first key 3

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enters the input of the second key 4 and the first input of the first switch 10. The latter compares the current amplitude value of the electrical signal, ·. arriving at its first input with a voltage from the output of source 12, proportional to the allowable value of the temperature supplied to its second input. If the current value of the electrical signal at the output 20 of the first key 3 is below the allowable,

¹ then the control input of the second key 4 from the first (inverse) output of the first comparator 10 receives a signal that opens the second key 4. At 25 this, the electrical signals from the output of the first key 4 arrive at the input of the peak detector 6, which stores the amplitude value of the electric signal proportional to - 30 maximum maximum temperature of the GTE working blade, currently in the sighting field of the photoelectric pyrometer 1, ^ Peak detector 6 is reset by signals from the output of the inverter 13 after passing of the working blade of the gas turbine engine in the field of view of the photoelectric pyrometer 1. From the output of the peak detector b, an electrical signal through the ADC 7, which converts it into a digital code, enters the alignment unit 8, which calculates the arithmetic mean of electrical signals proportional to the average maximum temperature of the gas turbine engine blades per revolution rotor.

From the output of the alignment unit 8, the signal enters the linearization unit 9, which linearizes the electrical output signal of the photoelectric pyrometer 1; At the output of the linearization block 9, the true temperature of the GTE rotor blades is obtained, which then goes into the engine automatic control system and zip into the recorder of flight parameters (not shown),

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In the event that the current value of the electrical signal at the output of the first key 3 is higher than the permissible value, the second (.inverse) output of the first comparator 10 receives a signal at the first input of the first integrato 14, the output of which produces a pulse whose amplitude is proportional to the duration of the output pulse the first comparator 10. The pulse from the output of the first integrator 14 is fed to the first input of the second comparator 11, the second input of which receives a pulse from the output of the second integrator 15, the amplitude of which is proportional to d the intensity of the pulse at the output of the shaper 20 measurement intervals, arriving at its first input. If the amplitudes of the pulses on the first and second inputs of the second comparator 11 are equal, a pulse appears at its output, arriving at the input of the standby multivibrator 17, and a signal is generated at the output of the working blade of the gas turbine engine overheating, entering the overheating indicator 18 and the third key control input 5, connecting the output of the counter 16 of the number of working blades to the input of the recorder of flight parameters, in which the number of the superheated working blade is recorded.

Resetting the first 14 and second 15 integrators, as well as the peak detector 6, is carried out by the falling edge of pulses from the output of the inverter 13 connected to the shaper 20 measurement intervals, the pulses at the output of which are formed as follows.

When the GTE rotor rotates, gauges pass by the position sensor 19, the number of which is equal to the number of blades mounted on the GTE rotor. pitch working blades at a controlled step. When passing the marker past the position sensor 19, pulses appear at its output, along which pulses are generated at the output of the measurement interval generator 20, the repetition rate of which corresponds to the frequency of occurrence of the working blades in the viewing zone of the photoelectric pyrometer 1, and the duration of the surface length of the working blade, on which temperature is controlled.

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The pulses from the output of the imaging unit 20 measurement intervals arrive at the control input of the first switch 3, which opens for a time equal to the pulse duration, and the output of the photoelectric pyrometer 1 through the amplifier 2 is connected to the input of the second switch 4 and the first input of the comparator 10. | 0

In addition, the pulses from the output of the shaper 20 measurement intervals arrive at the counting input of the counter 16 of the number of blades, the output of which forms the digital code number-15 of the blades located in the viewing zone of the photoelectric pyrometer 1. The blades are reset to zero 16 blades carried out · impulses from the output of the sensor 21 of the beginning of the 20th reference, formed at its output when the sensor 21 of the origin of the reference passes past the marker mounted on the shaft of the CCD.

When a photo- electric pyrometer 1 in the field of view interferes with signals caused by the presence of soot particles, the duration of which exceeds the time spent by one working blade in the viewing zone of the photo-30 electric pyrometer 1, the device will register the fact of overheating, recorded in the recorder of flight parameters.

In the subsequent processing of data recorded on repeatability in the DVR parameters flight numbers of rotor blades is determined by the record result of overheating of the _working: the blade or due to the presence Pomeranchuk dd hi the field of view of the photoelectric pyrometer 1.

Thus, the device allows you to determine the average maximum temperature of the GTE working blades for one revolution of the rotor, as well as fix the fact of overheating of any working blade, while achieving a higher temperature? Accuracy determination of the fact of the presence of overheating, as the signals of increased amplitude, recorded during the passage of the working blades in the sight zone of the photoelectric pyrometer 1, are additionally filtered by duration and repeatability.

Claims (1)

Claim A device for monitoring the temperature of the working blades of a gas turbine engine, containing a series-connected photoelectric pyrometer, an amplifier and a first switch, a position sensor and a measuring interval generator, a second switch, an analog-to-digital converter and a linearization unit, in order to improve accuracy determining the presence of overheating, it additionally contains a zero point sensor, a number of blades, reference voltage source, first and second comparators, first and second integral tori, divertor, standby multivibrator, overheating indicator, and alignment unit; the output of the first switch is connected to the input of the second switch and the first input of the first comparator, the second input of which is connected to the output of the voltage source, the first output of the first comparator is connected to the control input the second key, and the second output - with the first input of the first integrator, the output of which is connected to the first input of the second comparator, the second ·. ; · The input of the second comparator is connected to the output of the second integrator, and the output via the standby multivibrator is connected to the control inputs of the indicator and the third key, the input of which is connected to the output of the blade number, the output of the measurement interval driver is connected to the control input of the first key, the counting input of the number of workers blades, the first input of the second integrator and the input of the inverter. the output of which is connected to the control input of the peak detector and the second inputs of the first and second integrators, the output of the peak detector through • An analog-to-digital converter and an alignment unit are connected to the input of the linearization unit, and the output of the origin sensor is connected to the reset input of the blade number counter. 1488711